Electrical metal gathering machine



April 14, 1936. w. H. SPIRE 2,037,604

ELECTRICAL METAL GATHERING MACHINE Filed June 50, 1933 6 Sheets-Sheet l jg. J.

Wilz'am J5.

April 14, 1936. w. H. SPIRE I ELECTRICAL METAL GATHERING MACHINE Filed June 30, 1933 6 Sheets-Sheet Wham i i gym LK/ZL v April 14, 1935,

W. H. SPIRE ELECTRICAL METAL GATHERING MACHINE Filed June 50, 1933 6 Sheets-Sheet 3 April-14, 1936. w. H. sPlRE 2,037,604

ELECTRICAL METAL GATHERING MACHINE Filed June 30, 1933 6 Sheets-Sheet 4 d az're April 14, 1936. w sp ELECTRICAL METAL GATHERING MACHINE Filed June so, 1953 e Sheets-Sheet April 14, 1936. a. w s E -2,037,604

ELECTRICAL METAL GATHERING MACHINE Filed June 30, 1933 6 Sheets-Sheet 6 F2910 Z17 115 110 at; 114.

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gmmwtoz than A r. 14, 1936 STATES PATENT Application June 30, 1933, Serial No'. li78,531

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This invention relates to an improvement 01" the electric metal gathering machine described in my application for patent, Serial No. 234,159, filed on November 18, 1927, since matured into Patent No. 1,985,803, dated Dec. 25, 1934, and also my application for patent, Serial No. 566,205, filed on October I, 1931, since matured into Patent No. 1,961,256, dated June 5, 1934.

It is an object of this invention to provide an automatic machine in which, after a metal rod has been initially placed in contact with an abut- Inent electrode, or anvil, to be heated by current flowing through the rod and anvil, means for forcing the rod against the anvil to produce a final upsetting of the rod do not become operative until the end of the rod has reached a predetermined temper'ature and initial condition, and become operative when the end of the rod has reached the desired temperature and condition.

It is a further object my invention to so coordinate the temperature or" the end of the rod and the pushing efiort applied to the rod during the upsetting process that the shaped end will be free from corrugations or folds, and also free from such an internal structure condition and lack of homogeneity that is the result of the metal being fed into the upset portion at an improper rate.

It will be evident that if the metal is fed into the upset portion too slowly then that portion of the rod becomes unduly hot, while if it is fed too fast the cold metal entering the gather" reduces the temperature thereof unduly, and causes unduly high compressive forces that produce lateral spreading of the metal, and a misshapen head. In coordinating the pushing effort with he temperature of the upset portion 1 have produced an improved product, and have increased the production of the machine, while practically eliminating waste.

It is a further object of the invention to apply the heating current to initially heat the end of the rod in steps of predetermined current intensity. or in heating cycles, while a predetermined initial pressure is applied to the rod to condition the rod for the subsequent sustained and major application of force to produce the finished gather.

It is also an object of the invention-to provide an improved rodciamping electrode, and to provide means to coordinate movement of this electrode with movement of the means for applying longitudinal pressure to the rod.

It is also an important object of my invention to provide a yieldable abutment electrode ing cooperably connected thereto force applying means adapted to automatically retard mo merit of the abutment electrode while it is be pressed by the metal rod fed against it the gather-forming operation so that variations in the temperature of the heated rod are auto-- matically compensated for, within predeter=- mined working limits, to result in a gather the desired shape and condition.

While the invention is particularly described in its application to the production of gathers the end of a rod as a step in the forming cl valves, it wih be understood that the inst-lumentalities employed are readily available production of metal shapes by butt-Wei drawing, and by upsetting the metal at oint between its ends when the abutment electrode is provided with means to hold an end of a rod, or when means are provided to support a rod. he 7.. against the abutment, as the occasion denial it is also an important object of my invention provide a method of conditioning the gathered metal by selectively feeding a predetermined amount of rod into the gather while the heati: current is maintained or has been reduced in intensity, while the driving motor is decelerating at the end of the major gathering operation.

The complete processing of the rod may he thought of as comprising three steps, namely, so the first step of conditioning the end of the rod while it is at rest and is being heated by a current having an average value that is lower than normal, the second step of pushing the rod against the abutment while the heating current is normal intensity for the gathering operation, and the third step of determining the shape and temperature of the junction of the gathered ball with the rod while the pusher motor is decelerating as the result or its electrical circuit having been plugged, or otherwise conditioned to bring the motor quickly to rest.

Other and further important objects of this invention will be apparent from the disclosure in the drawings and the specification.

This invention, (in a preferred form), is more trated in the drawings and hereinafter more i described,

In the drawings: u

Figure 1 is a front view of a meta gathering machine embodying instrumentalities descrihc.. in connection with my invention.

Figure 2 is a front view of a portion of the ma chine of Figure 1, with parts in section and wi-.. parts broken.

Figure 3 is a diagrammatic view of the circuits and instnlmentalities employed in my invention.

Figure 4 is a diagrammatic view of a modification oi? the diagram of Figure 3.

Figure 5 is a front view of a modified form of the left end of the machine of Figure 1, with parts in plan, parts in section, and parts broken.

Figure 6 is a view of a detail of the means shown in Figure 5, with parts in plan, parts in section, and parts broken.

Figure 7 is a diagrammatic showing of the fluid pressure system for connection to the device of Figure 5.

Figure 8 is a side elevational view, with parts in plan and parts in section.

Figure 9 is a front elevational view of the device of Figure 8, with parts in plan, parts in section and parts broken.

Figure 10 is a diagrammatic showing of a fluid pressure system for connection to the device of Figure 8.

Figure 11 is a diagrammatic showing of a moclification of a part ofthe electric circuits. in Figures 3 and 4.

As shown on the drawings:

Figure 1 is a front elevation of an electric metal gathering machine described in my copending application for patent, Serial No. 234,159, filed on November 18, 1927, as seen from the operators position. The machine shown is adapted to upset one end of a short rod to form a ball or knob of metal which is subsequently forged in a heading machine to form the valve head of a poppet valve for internal combustion engines.

A metal rod ill is placed between the jaws it of a guiding clamp electrode l2, and one end the rod in is engaged by a boss IS on a pusher block I l. The boss I3 is shaped to receive the end of the rod and push it in alined relation through the guiding electrode pusher block H1 is moved by a screw l5 which is suit ably driven by gearing 16 connected to an electric motor l1.

After-the rod ID has been placed in position the motor I! is energized by the closing of a foot switch l8 to push the rod l0 through the electrode I2 against an anvil electrode IS. The anvil electrode is suitably arranged in, and insulated from. a housing 20, which housing is arranged for limited movement rearwardly against yieldable opposing means, as for instance, a spring 2 l, or a hydraulic buffer, which is described hereinafter.

After the rod has been advanced a predeter mined distance, and the abutment electrode has also been advanced a predetermined distance against the opposing means, switch means are actuated to stop the motor, and to energize a heating current circuit.

The rod used in the machine is usually a short length sheared from a long rod, and the contact resistance of the end is a variable quantity, depending upon the smoothness or roughness of the end. The nature of the alloy from which the rod is made also affects the contact resistance of the end, and slag-forming scale may be present on the surface of the rod. To avoid an excessive temperature at the contacting end of the rod the intensity of the current initially applied is made relatively low. Under the influences of the initial value of heating current and of the longitudinal pressure of the anvil electrode the end of the rod is gradually shaped to conform to the shape answer of the contact surface of the electrode, and the contact resistance is progressively decreased.

During this initial heating and metal conditioning period the heating current circuit may be interrupted and closed in cyclic order to produce alternate periods of heat application and heat diffusion, or the current intensity may be varied in cyclic order to produce substantially the same result. The current may be interrupted, for instance, when the end temperature reaches 1500 degrees, Fahr., and the cyclic variation be terminated when the temperature rises to, say, 2100 degrees, Fahr.

A photo-electric tube, or the like, is focused to be responsive to the radiant energy emitted at the contact point of the rod with the anvil electrode, and so observe the hot spot temperature of the rod; and the tube is mounted for movement with the anvil electrode. The term radiant energy is used in its broadest sense, and the observing device may he made responsive to energy radiated at many frequencies, or to a selected frequency, without departing from the spirit of the nvention.

the end of the rod conforms more and more to the contact surface of the anvil electrode, and the contact resistance decreases, the temperature of the rod near its contact point increases, because the heating effect varies as the square of the current, and, for a given secondary voltage, the current increases as the resistance of the circuit decreases.

When the temperature of the rod has reached a desired value the photo-electric tube, or the like, actuates connected electrical circuits and switches to increase the intensity of the heating current and to energize the pushing motor to advance the rod .against the abutment and thereby perform the major step in the gathering operation.

After the tube has performed its first function of delaying the increase of heating current intensity until good contact between the rod and the abutment electrode has been made certain, it is then conditioned, by the actuation of proper switch means, to take over the burden of coordinating the intensity of current flow and the rate at which the rod is advanced in the manner described in my copending application, Serial No. 566,205, filed on October 1, 1931.

When the rod has been advanced a sufficient distance to produce the desired gather at the end thereof the motor is plugged by a method familiar to electrical workers and which comprises sudden reversal of the power supply to the motor. The heating circuit may be interrupted at the instant of reversal of power supply to the motor so that the metal rod is fed into the heated gather by the decelerating motor and associated movable members, and the rate and extent of this final feeding movement may be nicely determined by the plugging operation to control the rate of deceleration immediately prior to reverse rotation of the motor. With rods of certain materials it is advantageous to delay interruption of the heating circuit until the motor has been plugged and its speed has been reduced to some predetermined value. The intensity of the heating current may also be reduced at the same instant as the motor is plugged, and the heating circuit subsequently interrupted when the motor speed has been rcduced to some predetermined value.

In general, it has been found desirable to so control the amount or"; rod feed after the motor Cir has been plugged that there is no reverse tolding or buckling of the metal at the rear end of the gather. The means described hereinafter are adapted to coordinate the temperature or the rod at the junction of the gathered ball and the original rod to cause a gradual tapering of the connection between the stem and the ball to avoid sharp angles and folds and thereby eliminate stresses likely to cause tearing of the metal.

The effectiveness of the plugging circuit used to stop the motor may be varied according to the temperature of the heated gather at the moment of plugging by suitably connecting the plugging circuit means with the tube, and thus the rate at which gather can be determined by the heat and mechanical treatment history of the gather.

Figure 2 illustrates a portion of the gathering machine at the forward, or anvil electrode end thereof. Forward movement of the electrode housing 20 is yieldingly opposed by plungers 22 slidable in cylinders 23 which house springs 2!. Forward travel of the housing 29 is arrested by the adjustably positioned cylinders 23, or by equivalent abutment means.

The electrode I9 is provided with a central core member 24 of a material adapted to withstand the sparking and arcing that occurs when the ragged end of the rod l0 first makes contact with the electrode.

It has been found that the life of the core material 24, is considerably increased when the tip of the metal rod is initially conditioned after the manner described herein.

A photo-electric tube 25 is positioned in a housing-25 which is provided with a focusing lens 21, and the housing 26 is mounted for move ment with the electrode housing 20, and the tube is so positioned, and focused, that it is responsive to the energy radiated at the tip of the rod or from the rear face of the central core 24, and also to the energy radiated within a fairly well defined short zone rearwardly of the tip of the rod.

A jaw ll of the clamping of rod-guiding electrode I2 is actuated for movement in a vertical direction by hydraulic means governed by the direction of rotation of the pusher motor l1 so that the jaw is automatically raised and lowered. The means for actuating the jaw II are described hereinafter.

In Figure 3 there are shown in diagrammatic form instrumentalities and connecting electric circuits employed in carrying out the invention. In Figures 3 and 4 an effort has been made to avoid confusion of lines, and it will be clear that the several switches and their connected circuits may be variously modified in amanner familiar to workers in the electrical art without departing from the spirit 9f the invention. The switch means for conditioning the several electric circuits can be conveniently assembled and housed in a cabinet 28, positioned above the machine.

Heating current for the rod ill, is supplied from power lines 29, to the primary 3!], of a transformer M, which has its secondary 32, connected to the electrode 12, and the electrode l9,

Power lfnes 33 supply the necessary energy for actuating the photo-electric tube 25 through an amplifier 34. The term amplfier is employed to broadly cover the instrumentalities necessary for the proper functioning of the tube and its auxiliary circuits, and includes expedients well known to those familiar with the electronic art.

the rod is fed into the When the operator has placed the rod to ing on the lower jaw of the opened jaws o electrode l2, he closes foot switch it; the ergizing the amplifier 34 and the actuatin of a switch 35 to close the power supply c' of the pusher motor ill, and cause the rod advance towards the anvil electrode tion or the motor I! causes actuation of hydraulic means, described hereinafter, to close the jaws H of the guide electrode i2. 71,

When the rod H! has advanced far enough cause a predetermined forward movement electrode housing 20, the power supply to the motor ll is interrupted by making use of the well known expedient of plugging of the motor, and the motor is brought to rest. Means for starting, reversing and electrically stopping the motor H are indicated generally by the numerals 36, for the sakeof simplicity.

The supply circuit of the motor may be inte rupted by means of a switch 37! and associate r lays, actuated by a stop member 3% on the trode housing 26, or by any other limitmeans responsive to initial. movement rod ill.

Upon a predetermined forward movement oi the electrode housing 2%, switch means are actuaated to cause current of relatively low intensity to flow in the circuit which comprises the rod and the guide and anvil electrodes, and such means may comprise a switch 39 actuated by stop member All on the electrode housing '20 to onergize the actuating coil of a switch ll and tliereb connect the transformer iii to the power lines in series with a conventional magnetic d2, provided with means for controlling satura of its care. For the sake of simplicity, core uration means are illustrated as compris-.. source of continuous current 63, and a poteiw tiometer 4d.

When, as heretofore described herein, the end of the rod ill has been shaped in the trode E9 to obtain good contact therewith, the photo-electric tube 25 actuates the potentiometer 44 through suitable actuating means db to d crease the reactance of the amplifier 62 thereby increasing the intensity of the heating current, and switch means 48, responsive to the control current for the amplifier cause the motor ii to start and thereby advance the rod ltl towards the anvil electrode i9.

Actuation of switch 16 also is effective to suit ably condition the circuit of the tube 25 by circuit conditioning means, indicated generally by the numerals Al, so that the tube 25 becomes efiective to control the temperature of the metal being gathered, within predetermined limits. through movement of the potentiometer control means When the rod it has been fed into the gather to Q produce a gather of the desired size the motor supply circuit is interrupted and reversed by switch 48 and associated relays actuated stop member $9 on the pusher block i:"3-,-the moior is pluggcd,and the heating current i quently interrupted by suitable switch i s or by a time-delay relay operatively connected to switch :8.

In Figure 11 there is shown diagrammaticallv a modification of Figure 3 to indicate means to whereby the 'heating current circuit may be selcctively interrupted after the motor is plo Instead of directly operating the line switch switches 39 and 3?), a conventiona bellows of relay, indicated generally by the numerals Cal may be inserted to control the operating circuit oi the switch ll. The relay is. provided with a pair of air valves arranged 56 that when the rel y is energized to move to circuit-closing position. i. is substantially no opposing force and the closing is instantaneous. However, when the relay is de energized to move to' the circuit-opening position, the valves are adjusted to admit air slowly to the bellows so that the break is delayed. It will now be clear that at the end of the major gathering operation, when the motor circuit is plugged by the operation of switch 39, or its equivalent, opening of the heating circuit is selectively delayed by the relay H, so that current is sent through the rod i0 for a predetermined time in the final step of tapering the rear end of the gather as the pusher motor decelerates. Other relays having an instantaneous make and a delayed break action will suggest themselves to those familiar with the electrical art, and may be employed without departing from the spirit of the invention.

As has already been described, due to its momentum, the motor i'i continues to feed rod it into the gather, and the amount of this feed may be nicely determined by the adjusting of the means for bringing the motor to rest and reversed.

Reversed rotation of the motor results in the opening of the jaws i I by the hydraulic operating means connected to the motor. The motor circuit is interrupted when the pusher returns to its original position, and when the operator then opens the foot switch l8 the motor control circuits are restored to their initial condition for readiness for the next gathering operation.

During the period in which the pho" eiectric tube 25 is conditioned to be responsive to the temperature of the metal, in the major gathering operation, the tube is connected to coordinate the temperature of the gathered metal with the heat ing current intensity and with. the speed, or torque, of the motor.

With a given current intensity in the heating circuit, if cold metal is fed too fast into the gather the temperature of the gathered mass is reduced. This reduction in temperature causes the photoelectric tube 25 to condition the transformer cir cuit to cause an increase in current intensity by actuating the potentiometer moving means 45. The tube may also be connected to vary the circuit intensity by varying the resistance or reactance of the power supply circuit through connected means described in the aforementioned copending application, Serial No. 566,205.

A magnetic amplifier is a quick-acting device, and, ordinarily, the heating circuit controlled thereby responds readily to the demand. for an increased current intensity to maint the gather at the proper working temperature.

Operating conditions may possibly arise, when, because of-low voltage of the power lines, the transformer cannot provide current of the intensity demanded, and if the motor is allowed to run at normal speed, and develop normal torque, the gather is defective. To meet such a condition, a time-delay switch 58 is connected to the tube 25": so that should the tube indicate an undesirable low temperature of the gather for an excessive period of time, time-delay switch 50 becomes effective to actuate a rheostat 5| and insert a resistance 52 in the motor circuit to decrease the speed and reduce the torque of the motor ii. The switch 50, may, of course, be arranged to progressively insert resistance in the motor cir suit, in a manner familiar to electricians, and to heating circuit to produce alternate heating and heat diffusion in the end of the rod it]. adapted to produce heating and heat diffusion cycles in the metal being heat treated are described in my application for patent, Serial No. 562,482, filed on September 12, 1931, since matured into Patent No. 1,985,804, dated Dec. 25, 1934.

In Figure 4, there is indicated generally a timed interrupter whicl. may comprise a step switch mechanism of a c adapted to open and close the circuit of the reactor the circuit of .ie y is urged. forward against a to, engaging the path oi a rack 5T, actu. a magnet 58. The wiper arm successively makes contact with a plur n ity of spaced contacts Retraction of the wiper arm 53 is prevented by a detent 53, and the arm is restored. to its original position when the detent G0 is by a releasing magnet El variable switch Gil movable lective y connected to any one of the s is put contact anvil electrode iii, the pusher motor is stopped, and the heating circuit is closed, in the manner already described. T en, by suitable circuit control mean ""5 circu 1 $3 is closed b;

switch Cu .l/ be tei'y 53 through th through a movable arm the pawl iii and through contact ccoperable with the pawl 55 to interrupt the circuit when the pawl is actuated to move the wiper arm 5t forward. one step.

When the battery circuit is interrupted the pawl will return to its normal position, and again the circuit is closed through the magn. cause a repetition of cycle. ment illustrated is clcly disgr a circuit 1'.

to shunt the battery circuit It will thus be clear is alternately entirely or substai ally interrupted. and restored in a predetermined munber of cycles to bring about cycles of heat ng and heat chiiusion in the end of the 0d wln'le it is pressed longitudinally by the spring it or other pressure means.

The periods of heating and heat diiiusion may be nicely adjusted by adjusting the inertia of the moving parts of the step-bystep mechanism, or the time constant of the actuating magnet 58, in a manner well known to those familiar with the electrical art,

The periods of heating and heat diffusion.

also be readily adjusted by making use of means substantially similar to that illustrated and described in my copending application, Serial No. 562,482, already referred to, namely, by employing the electron tube to interrupt the heating circuit when the temperature of the end of the rod reached a desired high value, and to restore the heating current when the tempera- At the termination of the major operation,

and, as the foot switch I8 is opened, suitable switch means are actuated to energize the release magnet 6| and to restore the step-by-step mechanism to its initial condition.

It will be obvious to those familiar with the electrical art that other timed means, such as a motor-operated interrupter, or an electronic oscillator device combined with a movable switch element may be substituted for the step-by-step switch mechanism described without departing from the spirit of the invention.

At the termination of the initial heat treatment of the rod l during which the end of the rod is brought to a desirable shape and condition, the photo-electric cell 25 then takes over the duty of controlling the gather in the manner already described herein, through the mediums of the potentiometer actuator 45 and the timedelay switch 58.

In Figure 5, there is shown a novel hydraulic check or buffer 68 to control and limit movement of the electrode housing 20, and to cooperate therewith in the initial conditioning of the end of the rod Ill, and in the subsequent operation of producing the gather.

Suitably secured to the bedplate 69 of the machine is a standard 10 through which pins H are slidable to carry the thrust of the electrode housing 28 to a yoke member 12. The pins H are provided with extending reduced portions I3 entered in suitable recesses in the yoke 12.

v A relatively long piston 14 bears against a central extending portion 15 of the yoke 12 and is provided with a. reduced forwardly extending portion 16 entered in a suitable recess in the yoke i2. The piston 14 is suitably packed to be oil tight but slidable in a cylinder H. The cylinder TI is provided with a slot "I8 so that the cylinder may be slipped over the yoke 12 to bear against the standard 10. The cylinder I! is secured to a piston 19, slidable in another, and larger cylinder 80, at the end of an extending neck 8|, by a nut 82, and the neck is provided with a port 83.

The port 83 communicates with the interior of the cylinders 17 and 8B, and with an accumulator, described hereinafter, through a port 84 in the cylinder 8|].

Studs 85 are threaded at one end in the standard I0, and engage the cylinder 80 at the other end to support and anchor the cylinder to the standard and thereby communicate thrust from the electrode housing to the frame of the machine. Suitable means, such as Woodruii keys 35, secure the studs 85 to the cylinder 80 to prevent spreading apart oi the studs under thrust conditions.

' Channeled portions 81 of the studs 85, pro vided with a semi-cylindrical bottom portion, provide a bearing for the pins H, and. an abutment for the rear end of the cylinder 89.

It will now be obvious that the hydraulic buffer is one that may be assembled with great ease. To assemble, the studs 85 are screwed into the standard iii, the pins 1| are inserted, the yoke ?2 is put in place, the cylinders are assembled in telescoped relation and 'slipped into position between the studs 85, and when a slight fluid pressure is applied to the piston 19 the parts take up their working position.

It will be clear that the cylinders are supported axially alined by the relatively long piston 14, which in turn is supported by the yoke '12 and the pins 1| slidably borne by the channeled portions 81.

Rearward thrust of the yoke 12 on the pins H, and through them to the electrode housing 28, is limited by abutment members, such as bosses 88 formed on the standard i0 adapted to engage the yoke 12 and thereby determine the extent of its rearward travel.

Figure '7 shows diagrammatically the piping lay-out connecting a conventional accumulator with the hydraulic buffer.

In Figure '7 an oil filled weighted accumulator 89 of a conventional type, with adjustable weights, is connected to the port 84 of the cylinder 80 by two pipes 80 and 9|, respectively.

In pipe 99 there is interposed a solenoid operated stop valve 92, which is normally closed, and a check valve 93 to prevent flow of oil from the hydraulic check 68 to the accumulator 89.

In pipe 9| there is interposed a spring-loaded needle-type relief valve 84 which also serves as a check valve to prevent flow of oil from the accumulator 89 to the hydraulic check 68.

The operation of the hydraulic buiifer is as follows:

With the yoke 12 bearing against the bosses 88 there is no pressure against the electrode housing 20, but the pressure in the cylinder holds the buffer assembly in assembled operative position.

The rod Ill is inserted between the jaws of the electrode l2, and the foot switch I8 is closed by the operator. The rod is then advanced to abut the anvil electrode l9, as heretofore described, and the electrode housing is thrust forward. Forward movement of the electrode housing 20 results in a thrust being transmitted through the pins H to the yoke 12, to the piston 14, and to the accumulator 89 by way of pipe 9|.

The force exerted by the accumulator is clearly that of the system pressure multiplied by the area of the piston 14, and this force is adjusted so that as the end of the rod becomes heated its irregular portions are upset at a rate to increase the contact cross-section and avoid overheating.

When the electrode housing 20 has moved a very short distance forward the pushing motor is stopped and the initial heating current is turned on in the manner heretofore described.

The movement of the yoke 12 is not enough, before the motor is again applied, to bring its bearing portion 95, rearward of the portion 75, into engagement with the surface 96 of the cy1- inder 'i'i terminating the slot 18, so that the force on the yoke '12 is that exerted by the smaller piston 14.

lit

iii

During the initial and of "o and "uring the conditioning period El'f actuated by movement of the pi close a circuit energizing the magnet and ihereb is-e opening of valve so that pressure y be exerted by the ac-- cumulator The switch 91 may be connected for movement with a clamping electrode I02, to be described later, or otherwise connected to a movable part of the machine to cause the functioning of the valve 92 at the proper time. Oil that has been iorcedout of cylinder 11 by movement of the piston M has passed by pipe 9| through relief valve 4 to the accumulator 89.

At the end. or" the conditioning period .of the tip of the rod, the motor is again started and the electrode housing is pushed forward, and the yoke I2 is pushed lt'orw rd to engage and move the cylinder H. At the moment that cylinder TI, and with it piston begins to move forward this motion is suddenly retarded because of the larger volume of oil being displaced and forced through the needle valve 9d against increased spring pressure the valve is lifted. Thus. further movement .r the pusher block Id results in the opening of the switch S3? and thus closes the magnetoperated valve 92.

It will be clear that during the conditioning period the accumulator B9 was effective-to apply pressure to the small piston I4 because the valve 92 is open, but that during the subsequent forward movement of the rod ID the needle valve 94 determines the rate of movement of the electrode housing 20 because valve 93 prevents return flow of fluid by way of pipe 90.

Because of the increased retarding force a.pplied to the housing 20 by the hydraulic buffer during the gathering operation it follows that the gather on the end of the rod increases rapidly. As the gather increases in size, because of the heated rod l8 being urged forwardly by the pusher is against the anvil IS, the piston T9 moves forward with increasing rapidity, and the pressure against the piston also increases. However, should the rod I0 upset too readily the pressure required for upsetting is less, and since the electrode housing 28 will then move more slowly, relative to the rod, the rod is fed into the upset with relatively increased rapidity with a consequent reduction in the temperature of the gather. On the contrary, if the rod does not heat readily the pressure required to upset the rod is greater than normal, the speed of the electrode housing 28 relative to the rod is increased, the retarding force is automatically increased to upset the rod, and since the length of the rod between the electrodes increases at more than a normal rate the resistance of the work portion of the rod is correspondingly increased with a compensating increase in temperature, since the heating depends upon the square of the current multiplied by the resistance of the work portion.

It will now be clear that the hydraulic buffer p ovides a simple means for automatically adjusting the pressure to meet changes in the contour of lhe heated end of the rod while the end of the rod is being initially conditioned.

It will also be clear that the hydraulic buffer prov des simple means for automatically compensating for such variables as the hardness of the and the voltage and heating effect of the supply circuit, within controlled limits, during the gatherfng operation.

The s andard 70 provides an abutment to limit iorward movement or the elcctrodehousing 2B,

movement of the pusher 2,

and shims 98, or similar abutment means, may be positioned on the rear side of the standard to limit the forward movement of the housing 20. When the electrode housing 23 has moved forward a predetermined distance the motor I! is plugged by the actuation of suitable switch means, in a. manner heretofore clearly described herein, and the pusher I 4 is retracted. As the pusher is moving rearwardly to its initial position it actuates the switch 97 to energize the magnet of valve 52 and so open this valve for a predetermined time to cause the pressure of the accumulator 89 to return the electrode housing 28 to its initial position, and care is taken to permit suiiicient time for the operator to remove the rod before the housing is returned by the closing of the switch 91.

It will be obvious that a source of fluid pressure other than the accumulator 89 may be provided. It will also be clear that the valve 94 may be manually adjusted during the metal working operation, or may be adjusted by a. lever and cam mechanism connected to a moving part of the hydraulic check so that the machine may be used to work metal members of various sizes and shapes.

The rod clamp I I comprises a stationary lower jaw 99 and a hinged upper jaw IOU each of which is provided with a conducting insert, IIlI of copper or other suitable material. The jaws are suitably supported by a standard I02 mounted on the frame of the machine.

Also suitably supported in the standard I02 is a hydraulic clamp actuating device, indicated generally by the numerals M3. The device I03 comprises a. frame I04 having a runway defined by a curved guide rail I05 providing spaced opposed vertical elements and continuing lower inclined and spaced elements terminating in a curved toe. A pair of rollers I06 slide guided on the guide rails, and the rollers are held in assembled relation by a pair of connecting side links Hill.

The rollers are adapted to be pushed downwardly by a piston H18 in a bore I09 of a cylindrical structure ill) by a link III pivotally connecting the piston I08 with the rollers.

The rollers are adapted to be moved upwardly by a piston I I2 in an upper bore I I3 of the cylindrical structure IIO through a link II i pivotally connected to the upper piston and to the lower piston.

Intermediate between the lower and upper bores in the structure H0 is a. solid portion II5 having passages H6 and H7 communicating with the lower and upper bores respectively, and connected to pipes H8 and H9 respectively, which are threaded in the solid portion.

The pipes H8 and H9 are connected to a gear type of pump I20, and in the operation of the pump, as described hereinafter, each of the pipes become alternately suction and discharge lines of the pump. A pipe loop IZI is connected to the pipes IIS and II9, and a pipe I22 connects the loop with an open oil reservoir 23. In the loop I2I there is interposed a pair of check valves F24 and I25 to prevent flow of oi towards the reser voir. A relief pipe I26 is connected to the pipes H8 and H9 to discharge oil to the tank, and

between its connections with the pipes there are F interposed check valves I2! and I28 to prevent the discharge of the pump from passing from the discharge line to the suction line. In the relief pipe I26 there is interposed a weighted relief valve H49.

The pump I may be driven by the pusher motor 'I'T'through gears or other suitable means so that when the pusher motor is reversed the pump is also reversed. When the pusher motor I1 is rotated to advance the rod I0 against the anvil electrode I9 the pump sucks oil through pipe H9 and discharges it under pressure through pipe H8 thereby pushing the piston I08 down or pulling down ,the piston II2.

It will be clear the suction side of the pump is always in communication with the open reservoir I23 to replenish the pressure part of the system in the event of loss of oil through leakage.

As the piston I08 descends and with it the rollers, I06, a rod I pivotally connected to the rollers and to the upper jaw I00, moves downwardly to close the clamp II.

It will be clear that when the piston I08 was in its initial position near the upper end of the bore I09 the link connection between the piston I08 and the rod I30 was straightened out. As the piston I08 descends and the rollers I00 are swung out of line as they roll on the inclined portion of the runway there is a force-multiplying effect, and when the rollers reach the end of their downward, travel the upper portion of the runway takes the longitudinal thrust of the rod I30 so that the means described become a lock. The means described are therefore force multiplying and locking means.

It will now be evident that when the motor I1, and the pump I20 rotate in a reverse direction, oil is sucked from the bore I09 and forced into the bore H3, resulting in upward movement of the two pistons, and the opening of the clamp I i.

The pump I20 may be directly connected to a motor I3I for individual drive and this motor may be suitably connected to be energized through the actuation of switch means I32 to cause the pump motor to start and stop, in step with the pusher motor H.

In the operation of the gathering machine the initial position of the pusher I4 is usually such that the hydraulically operated clamp has closed before the pusher makes contact with the rear end of the rod I0.

It has been found that because of the manner of applying force to the movable jaw I00, the clamp is practically self-adjusting and accommo dates itself so that firm contact between the copper inserts of the clamp and the metal rod I0 is obtained even though the size of the rod is varied within operating limits. Were an unusually large size of rod placed between the jaws having inserts best adapted for smaller rods, it is evident that the larger size of rod would be yieldingly, although firmly held between the jaws. The straight-line thrust of the rod I30 against the upper side of the runway would be somewhat less than usual, but there would still be a pronounced locking efiect.

It will be obvious to those familiar with the metal working art that the invention may be readily applied to other metal working operations in which it is desirable to coordinate the temperature of the heated metal with the longitudinal pressure applied thereto. It is contemplated that the invention will be applied to such metal working operations as butt-welding, up-

setting and drawing by making use of well known expedients to clamp both ends of the rod in the drawing operation, or to hold and support the rod or rods in the upsetting and butt-welding operations, respectively. The metal at the heated portion to be worked into the desired shape may be heading machine which receives the hot gathered rods discharged from the gathering machines. Because of the uniform quality of the product of the metal gathering machine, and of uniformity in the time taken by the machine to do the task required of it, it has been found possible to interconnect the machines of a battery for interlocked operation so that there is a uniform flow of the product to the heading machine. When the duty on the heading machine is substantially constant there is a marked increase in the life of the dies of that machine, and there it also a smoother load curve on the power system.

I am aware that many changes may be madeand numerous details of construction may varied through a wide range without departing from the principles of this invention, and I, therefore, do not propose limiting the patent granted hereon otherwise than necessitated by the prior art.

What I claim is:

1. In combination, a movable abutment electrode, means to firmly hold a rod substantially at rest, pressure means connected to press said abutment electrode against an end of the rod, an electric circuit for heating the rod, means to condition the circuit for a current intensity of a predetermined effective value while the rod is at rest, means to push the rod and thereby effect movement of said abutment against said pressure means, and means to condition the circuit for a higher current intensity while the rod is moving.

2. The method of working a metal rod heated by current in an electric circuit, said method comprising the steps of applying a predetermined pressure to an end of the rod while a heating current of a predetermined intensity is passed through the end to initially condition that end, then increasing the applied pressure and increasing the intensity of the current to form a gather on the end of the rod.

3.-In combination, a movable abutment electrode, means to push a rod against said abutment, electric circuit means to heat the rod, pressure means connected to press said abutment against an end of said rod, and means movable with said abutment to selectively retard movement of said abutment.

4'. In combination, a movable abutment, means to push a rod against said abutment, electric circuit means to heat the rod, pressure means connected to press said abutment against an end of said rod, and means adapted to selectively co ordinate effectiveness of said pressure means with v the movement of said abutment.

5. In combination, a movable abutment, pusher means movable to push a rod against said abutment, electric circuit means to heat the rod, pressure means connected to press said abutment against an end of the rod, and means responsive to movement of said abutment by said rod to selectively vary the effectiveness of said pressure means. I

B. In combination, a movable abutment, pusher means movable to push a rod against said abutment, electric circuit means to heat the rod, pressure means connected to press said abutment against an end of the rod, said pressure means including piston means movable to selectively retard movement of said abutment and movable with said abutment.

'7. In combination, a movable abutment, pusher means movable to push a rod against said abutment, electric circuit means to heat the rod, pressure means connected to press said abutment against an end of the rod, and means responsive to the rate of movement of said abutment eifective to vary the pressure applied by said pres sure means.

8. In combination, pusher means movable to app'y longitudinal pressure to one end of a rod to cause forward movement of the rod, pressure means including a movable abutment connected to apply longitudina. pressure to the other end of the rod and thereby retard forward movement of the other end of the rod, electric circuit means to heat the rod, and a plurality of connected pistons movable with said abutment connected to selectively retard forward movement of the rod.

9. In combination, means movable to apply force longitudinally to a rod to cause movement of the rod in one direction, other means movable to apply force longitudinally to the rod to cause movement of the rod in an opposite direction, electric circuit means to heat the rod, said other means including a piston and a cylinder housing said piston and movable therewith.

10. In a machine for applying force to heated metal to be worked, electric circuit means to heat the metal, means to apply pressure to the metal in one direction, other means to apply pressure to the metal in an opposite direction, said other means including a source of fluid under pressure, a pair of connected pistons, and a cylinder housing one of said pistons and movable therewith.

11. In a machine for applying force to heated metal to be worked, electric circuit means to heat the meal, means to apply pressure to the metal in one direction, other means to apply pressure to the metal in an opposite direction, said other means including a source of fluid under pressure, a piston having a cylinder connected thereto for movement therewith, and another piston movable in said cylinder.

12. In combination, a movable abutment, means to push a rod against said abutment to cause movement of said abutment in one direction, electric circuit means to heat the rod, pressure means connected to retard movement of said abutment, said pressure means including a source of fluid under pressure, a piston having a cylinder connected thereto for movement therewith, and another piston movable in said cylinder.

13. In a metal working machine, means to hod the metal to be worked against movement, an anvil adapted to shape the metal, means to press said anvil against the metal, said means comprisinga source of fluid under pressure, a piston having a cylinder connected thereto for movement therewith, and a piston movable in said cylinder.

14. In a metal work ng machine, means to hold the metal to be worked against movement, an anvil adapted to shape the metal, electric circuit means to heat the metal, means to press said anvil against the metal, said means comprising a source of fluid under pressure, a piston having a cy nd r connected thereto for movement thereu' and a piston movable in said cylinder.

15. In combination, a movable abutment electrode. pusher means to push an end of a rod against said abutment electrode, electric circuit means to heat the abutting end of the rod, and means movable with said abutment electrode connected to said electric circuit to selectively condiiion said electric circuit and thereby maintain the temperature of the end of the rod within predetermined limits.

16. In combination, a movable abutment elec trode, pusher means to push an end of a metal red against said abutment electrode, electric circuit means to heat the abutting end of the rod, and electron tube means movable with said abutment electrode connected to said electric circuit to selectively condition said electric circuit and thereby maintain the temperature of the end of the rod within predetermined limits.

17. In a metal gathering machine, a movable abutment cectrode, means to hold an end of a metal rod in abutting relation to said abutment electrode, pressure means connected to press said abutment electrode rearwardly against the end of the rod, electric circuit means to heat the rod, means connected to said electric circuit to initially condition said circuit to thereby produce alternate heating of and heat diffusion in said rod for a predetermined number of cycles, and pusher means connected to push said rod against said abutment electrode and thereby cause for- Ward movement of said abutment electrode at the termination of the initial heat treatment period.

18. In a metal gathering machine, a movableabutment electrode, means to hold an end of a metal rod in abutting relation to said abutment electrode, pressure means connected to press said abutment electrode rearwardly against the end of the metal rod, pusher means arranged ener- 5 gizable to push the rod against said abutment electrode and thereby cause forward movement of sa d abutment, means responsive to a predetermined forward movemcnt of said abutment elec trode connected to ole-energize said pusher means, electric circuit means to heat the rod, and means to iniiially condition the end of the rod in contact With said abutment electrode, said means comprising an electron tube movable with said abutment electrode connected to said electric circuit to condition said circuit for current flow of a prered, said means including means connected to said electric circuit to condition said circuit to thereby produce alternate heating of and heat diffusion in said rod for a predetermined number of cycles, and pusher means arranged to push the rod against said abutment electrode and thereby cause movement of said abutment in an opposite direction at the termination of the conditioning heat treatment.

20. In the method of producing a gather on an end of a heated metal rod which is a part of an electrfc heating circuit, the steps of initially heating the end of the rod with current of a moderate intensity while the end is pressed by an anvil electrode under moderate pressure. and then subsequently increasing the pressure and the current intensity, each to a higher value, to produce the gather.

21. In the method of producing end of a heated metal rod which electric heating circuit, the steps a gather on on is a part of an of feeding the Ell aces eccrod against an anvil electrode while the rod is heated by electric current, to produce a gather, and then feeding a predetermined amount of the rod into the gather after the heating circuit has been interrupted,

22. In the method of producing a gather on an end of a heated metal rod which is part of an electric heating circuit, the steps of feeding the rod against an anvil electrode while the rod is heated by an electric current, and then feeding a predetermined amount of the rod into the gather after the heating current has been substantially reduced.

23. In a metal gathering machine in which a heated metal rod is fed against an abutment electrode to produce a gather, an abutment electrode, pusher motor means connected to feed a metal rod against said abutment electrode, electric circuit means to heat the rod, an electric circuit for said motor, switch means operative to condition said motor circuit to produce deceleration of said motor and subsequent stopping thereof, and timed means connected to interrupt said heating circuit during the period of deceleration of said motor.

24. In the method of producing a gather on the end of a heated metal rod which is part of an electric heating circuit, the steps of feeding the rod against an electrode at one speed while the rod is heated by an electric current to produce a gather of metal on the end of the rod, then feeding the rod at a decelerating rate, and then interrupting the heating circuit during the period of deceleration.

25. in a metal gathering machine in which a heated metal rod is fed against an abutment electrode to produce a gather, an abutment electrode, pusher motor means connected to feed a metal rod against said abutment electrode, an electric circuit for said motor, an electric circuit to heat the rod, switch means actuable to condition said motor circuit to produce deceleration of said motor and subsequent stopping thereof, and switch means for said heating circuit connected with said first switch means to selectively maintain said heating circuit during deceleration of said motor.

26. In a metal gathering machine in which a heated metal rod is fed against an abutment anvil.

electrode to produce a gather, an abutment elec-.

trode, pusher motor means connected to feed a' metal rod against said abutment electrode, electric circuit means to heat the rod, means to interrupt the, heating circuit during the gathering operation, and means connected to control said pusher motor to cause a predetermined amount of the rod to be fed into the gather after the heat- Ling circuit has been interrupted.

2'7. A metal gathering machine comprising an abutment, a clamp having a movable jaw, pusher means connected to push a metal rod through said clamp to abut said abutment, said pusher means being reversible in direction, and means connecting said pusher means and said jaw to cause closing of said clamp when said pusher means move in one direction and opening of said clamp when said pusher means move in an opposite direction.

28. In a metal gathering machine, an abutment, a clamp having a movable jaw, a pusher adapted to push a rod through said clamp to abut said abutment, said pusher being reversible in its direction of movement, motor means connected to actuate said jaw and being reversible to open and close said jaw, respectively, said pusher and said" motor means being connected for conjoint move:

ment.

29. In a metal gathering machine, an abutment, a clamp, a pusher adapted to push a metal rod forwardly through said clamp to abut said abutn'ient, said pusher being adapted to move forwardly and rearwardly, motor means reversible to close and open said clamp, respectively, and means connecting said pusher and said motor means to cause closing of said clamp when said pusher moves forwardly and opening of said clamp when said pusher moves rearwardly.

30. In a metal working machine, a first electrode and a second electrode, said electrodes being adapted to engage a metal rod positioned therebetween, electric circuit means connected to said electrodes to heat the rod, means to apply opposing forces to said electrodes, and an electron tube mounted movable with one of said electrodes, said electron tube being responsive to energy emitted by the heated metal rod and being connected to said electric circuit to condition said circuit and thereby maintain the temperature of the rod within predetermined limits.

31. In a metal working machine, a first electrode and a second electrode, said electrodes being adapted to engage a metal rod positioned therebetween, electric circuit means connected to said electrodes to heat the rod, pressure means connected to said first electrode to produce movement thereof and simultaneously apply force along the horizontal axis of the rod, and electron tube means responsive to energy emitted by the heated rod connected to condition said electric circuit for variable current flow, said electron tube means being arranged movable with said first electrode.

32. In a metal working machine, a first electrode and a second electrode, said electrodes being adapted to engage a metal rod positioned therebetween, electric circuit means connected to said electrodes to heat the rod, pressure means connected to said first electrode to produce movement thereof, and simultaneously apply force along the longitudinal axis of the rod, timed means connected to said electric circuit to condi tion said circuit and thereby produce alternate cycles of heating of and heat diffusion in the metal rod for a predetermined period, and other pressure means connected to said second electrode to produce movement of both of said electrodes andof the rod at the termination of said period.

33. L1 a metal working machine, an abutment electrode, a clamp electrode adapted to clamp a rod to be pushed through the clamp to abut said abutment electrode, electric circuit means connected to said electrodes to heat the rod, electric motor means connect-ed to push the rod through said clamp electrode, other electric circuit means to energize said motor, means to interrupt said heating circuit, and means connected adapted to condition said other electric circuit "means for movement of said electric motor to push the rod for a predetermined period aft/er said heating circuit has been interrupted.

3 in a metal working machine, a, movable abutment electrode, a clamp electrode, pusher means adapted to push a metal rod through said clamp electrode to engage said abutment electrode and produce forward movement thereof, fluid pressure means connected to said abutment electrode comprising a hydraulic bufier, a source of fluid pressure, a pipe connecting said source and said buffer, and a valve in the pipe, and means adapted to actuate said valve upon movement of said pusher means to selectively control fluid flOW to said butter and thereby selectively retard forward. movement of said abutment.

in a metal working machine, a movable abutment electrode, a clamp electrode, pusher means adapted to push a metal rod through said clamp electrode to engage said abutment electrode and produce forward movement thereof, fluid pressure means connected to said abutment electrode comprising a hydraulic buffer, a source of fluid pressure, a pipe connecting said source and said buffer, and a weighted relief valve in the pipe, means to selectively control fluid flow between said source and said bufier to thereselectively retard forward movement of said abutment electrodes, said means comprising a second pipe connected in parallel with said first named pipe, and a valve in said second pipe connected to be actuated upon movement of said pusher means. a

36. In a metal gathering machine, a first electrode and second electrode, said electrodes being to engage a metal rod positioned thereioetween, electric circuit means connected to said electrodes to heat the rod, and electron tube means connected for movement with one of said electrodes, said electron tube being responsive to energy emitted by the heated rod and being connected to affect current flow in said electric circuit.

3?. In a metal gathering machine, a movable abutment electrode, a yoke connected to said electrode, a piston connected to said yoke, 3. cylinder housing said piston and adapted to be moved by said yoke, another piston connected to said cylinder for movement therewith, another cylinder housing said other piston, a source of fluid under pressure, and conduit means connectsaid pistons in fluid communication with said metal gathering machine, a movable abutment electrode, pressure means adapted to move said electrode, said pressure means comprising a source of fluid under pressure, :1 cylinder connected in fluid communication with said source, a hollow piston slidable in said cylinder, said hollow piston having a port for fluid, another piston slidable in said hollow piston, a yoke connected to said other piston and being adapted to move said, hollow piston, and a connection between said yoke and said abutment electrode.

39. In a metal working machine, a first. cylinder, a second cylinder movable in said first cylinder, a piston movable in said. second cylinder, a movable electrode connected to said piston, said second cylinder being arranged for selected movement with said electrode, and fluid pressure means connected in fluid communication with said cylinders and said piston.

40. In a metal gathering machine, a movable abutment electrode, movable pusher means adapted to push a metal rod against said electrode and thereby effect movement of said electrode in one direction, fluid pressure means connected to said electrode, and means connected operable upon a selected movement of said pusher means adapted to control said fluid pressure means to effect movement of said electrode in an opposite direction.

41. In a metal gathering machine, a movable abutment electrode, movable pusher means adapted to push a metal rod against said electrode to thereby effect movement of said electrode, fluid pressure means connected to said electrode, and means responsive to movement of said electrode connected to selectively vary the pressure exerted by said pressure means.

WILLIAM H. SPIKE. 

